Machine for sharpening taps and dies.



A. H. GRAB MACHINE FOR SHARPBNING TAPS AND DIES.

APPLICATION FILED JAN. 15, 1910.

Patented Feb. 14, 1911.

mp NaRRls PETERS co., WASHINGTON, n. c.

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ANTHONY H. GRAEF, OF DETROIT, MICHIGAN, ASSIGNOR TO RAYMOND S. TOLSIVIA, OF DETROIT, MICHIGAN.

MACHINE FOR SHARPENING TAPS AND DIES.

To all whom it may concern:

Be it known that I, ANTHONY H. Gnanr, a citizen of the United States, residing at Detroit, county of ayne, State of Michigan, have invented a certain new and useful Improvement in Machines for Sharpening Taps and Dies, and declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it pertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

My invention relates to machines for grinding taps and dies and has for its object means for re-sharpeni'ng the dies whereby their cutting edges when dull may be quickly restored to normal condition without the necessity of first annealing the die before sharpening with a file as usually employed.

Another feature is the means employed to hold the grinding pencils, whereby if the grinding pencil in commission is not of the right diameter it may be quickly removed and replaced with one adapted to meet the requirements of the die to be sharpened.

Other advantages and improvements will hereafter appear.

In the drawings accompanying this speci fication: Figure 1 is a side elevation of the grinder showing a die and tap in position to be sharpened. Fig. 2 is a central vertical section of the machine. Fig. 3 is a side elevation of the die showing the grinding penoil in cross-section in position to sharpen the same. through a tap showing a fragmentary view of the grinding wheel in position to sharpen the tap.

Referring now to the letters of reference placed upon the drawings: A is the base of the machine provided with up-standing annular arms A in which are set ball bearings B.

C is a shaft ournaled in the bearings and threaded at one end to receive a split chuck D adapted to receive the end of a grinding pencil E.

D is a nut engaging the tapering end of the chuck to force the split walls forming its jaws into binding relation with the pencil.

F is a cap having a screw-threaded engagement with the annular arms A,the

inner end of the cap bearing against the race of the ball bearlng B.

Specification of ietters Patent.

Application filed January 15, 1910.

Fig. 4: is a longitudinal section" Patented Feb. 14, 191i.

erial No. 538,182.

F is a felt washer encircling the inner end of the chuck D and supported in the recess provided in the cap F.

f is a perforation in the cap F leading from the washer to the chambered portion f, the latter being adapted to hold a lubricant. On the opposite end of the shaft C is mounted an emery wheel G secured to the shaft by means of suitable hub plates g and the nut g engaging the end of the shaft.

H is a cap encircling the shaft and having a screw-threaded engagement with the other lip-standing annular arm A. Housed within the cap H is a felt washer h encircling the shaft.

h is an aperture formed in the cap H leading from the recess in which the felt washer is housed to the chambered portion 7L2 of the cap, where a suitable lubricant is held. Vithin the recessed portion of the cap and between it and the ball race is a nut H adjusted so as to bear directly against the ball race.

H is a nut-lock formed of spring wire engaging the shaft at one end; the other end embracing the nut.

I and I are felt washers housed within recesses formed in the tip-standing annular arms A and bearing upon the shaft-,the purpose of the several felt washers being to retain the lubricant within the bearings, as will be readily understood.

J is a driving pulley secured to the shaft by the screw J.

K shows a die in position to be sharpened and L is a tap in the act of being sharpened.

Having indicated the several parts by reference letters, the operation of the machine will be readily understood.

hen sharpening a die in the usual manner, it is necessary to anneal it before it can be filed. The filing is a somewhat long and tedious job and seldom results satisfactorily,-as in the annealing and subsequent hardening process, the threads of the die are apt to warp out of shape, frequently making it necessary to throw it in the scrap heap.

To sharpen a die by the use of my ma chine it is only necessary to select a grinding pencil of the proper size and secure it in the chuck D by adj ust-ing the nut D along its tapering wall, thereby forcing it to grip the pencil. The die is then held in position over the pencil as indicated in Figs.

1 and 3 and the machine started, which is run at a very high rate of speed.

In sharpening a die it is quite essential that there be no end play of the grinding pencil. It will therefore be noted that the chuck D bears directly against the ball race which in turn bears upon a shoulder formed in the shaft C and also the annular wall of the upstanding arms. The annular rim of the cap F also bears against the ball race holding it secure against the wall of the arm and thus preventing endwise movement of the pencil. A somewhat similar arrangement prevails at the other end of the ma chine except that the annular rim of the cap H does not bear against the ball race in order to avoid binding the bearings which may result from careless adjustment.

To sharpen taps, they are held against the grinding wheel in the position shown in Figs. 1 and t,-the wheel entering the longitudinal grooves of the tap.

Having thus described my invention, what I claim is 1. In a machine of the character described,

a frame, a drive shaft journaled in the frame,

means for driving the shaft, a chuck mounted on one end of the shaft, an abrasive element supported by the chuck, and an annular chambered cap sleeved on the chuck I and adapted to hold a lubricant, said cap l carrying a gasket in spaced relation to said chambered portion, the cap having a channel leading to the gasket to its chambered portion to convey lubricant to the gasket.

2. In a machine of the character described, a frame, ball bearings supported in said frame, a drive shaft journaled in the bearnular chambered cap sleeved on the chuck mounted on the end of the shaft provided with a projecting annular tapering end, the wall of which is longitudinally divided, an abrasive element supported in the chuck, a nut having a screw-threaded engagement with the tapering end of the chuck, an annular chambered cap sleeved on the chuck adapted to hold a lubricant and having a screw-threaded engagement with the frame, said cap also provided with a recessed por tion adapted to house a gasket, a channel leading from the recessed portion of the cap to its chambered portion, and a gasket housed in said recessed portion.

In testimony whereof, I sign this specification in the presence of two witnesses.

ANTHONY H. GRAEF.

lVitnesses SAMUEL E. THoMAs, RAYMOND S. TOLSMA. 

